i) Field of the Invention
This invention relates to a diagnostic method and apparatus for assessing lung tissue of a living subject; more especially the invention is concerned with such a method and apparatus employing ultrasonic radiation.
ii) Description of Prior Art
Ultrasound has been used in medical, industrial and other environments, and various systems and methods have been employed.
Single element ultrasound systems have been used to pass ultrasonic waves into the human body, for example, as part of an evaluation of the state of health of body organs.
These systems provide real-time, time of flight, reflectance images of the body organs.
Ultrasound systems have also been employed in therapy.
Various proposals have been made for use of reflectance ultrasonic assessing of the lung, but none of these proposals permit real-time assessing, so as to be effective with continuous breathing.
There is a particular need for diagnosis aids which will provide medical diagnostic information relating to diseases and disorders of the lung, for example, emphysema, asthma and disorders resulting from use of tobacco products.
At present diagnosis of the number and size of airspaces in the human lung requires the use of costly medical imaging equipment such as CT or MRI. With such equipment it is not possible to assess the lungs dynamically, in other words it is not possible to assess the changes in the airspaces during breathing.